Improvement in the manufacture of sheet-iron



W (time. a

co. H'INSDALE, OF,

CLEVELAND, OHIO.

Letters Patent No. 89,312, dated April 27,1869.

IMPROVEMENT IN THE MANUFACTURE OF SHEET-IRON. I

The Schedule referred to in these Letters Patent and making part of thesame.

To all whom it may concern:

Be it. known that I, G. O. HINSDALE, of Cleveland, in the county ofUuyahoga, and State of Ohio, have invented certain new and usefulImprovements in the Process of Manufacturing Sheet-Iron; and I do herebydeclare that the following is a full and complete description of thesame.

I am aware that the process of cementing has been known and usedheretofore, but this I do not claim.

The nature of my invention relates to the process of semi-carbonatingsheets of iron, and rendering them susceptible of receiving a smooth andhighly-polished surface when passed between rollers.

The iron is first rolled from the common sheet-bar to a sheet, thethickness of which is from N0. 18 to 24 wire gauge, more or less, as maybe required. It is then thoroughly annealed in the ordinary manner, orby any other suitable means. The sheets are then cleaned in a commonacid-bath, or its equivalent, for the purpose of removing all oxides,dirt, and scale.

They are then packed in a east-iron box or case,

charged with charcoal, or other carbonating agents, which are placedbetweeuand around the plates. I

The box is then placed in an ordinary mufile-furnace, and submitted tothe action of a heat of about 1000 more or less, as maybe foundnecessary, for two or three hours, for. the purpose of semi-carbouatingthe sheets.

The box is then removed from the furnace, and allowed to cool slowly.The sheets are then heated to a dull red heat, and passed betweenrollers sufficiently to give them a smooth and polished surface.

What I claim as my improvement, and desire to secure by Letters Patent,is-

The herein-described mode or process of preparing sheet-iron forrolling, whereby a highly-polished surface is given to saidsheets, bythe means and in the manner substantially as set forth.

' O. O. HINSDALE. Witnesses:

W. H. BURRIDG-E, E. E. WAITE.

